Multiplication Puzzle，区间dp

l是长度，k是中间位置，j是终点，从1到3开始，长度是3

#include<stdio.h>
#include<string.h>
#include<math.h>
#include<stack>
#include<algorithm>
#define mem(a,b) memset(a,b,sizeof(a))
const int N=202;
typedef long long ll;
using namespace std;int a[N],dp[N][N];
int main()
{
    int n;while(~scanf("%d",&n)&&n){
    memset(dp,0,sizeof(dp));for(int i=1; i<=n; i++)scanf("%d",&a[i]);for(int l=3;l<=n;l++){
    for(int i=1;i+l-1<=n;i++){
    int j=i+l-1;dp[i][j]=9999999;for(int k=i+1;k<j;k++){
    dp[i][j]=min(dp[i][j],dp[i][k]+dp[k][j]+a[i]*a[k]*a[j]);}}}printf("%d\n",dp[1][n]);}return 0;
}